Conveyor system controller, conveyor system and method of data synchronization

Abstract

The present disclosure provides a conveyor system controller ( 11, 12, 13, 14 ), comprising: a data storage unit ( 101 ) configured to store a plurality of data entries, each data entry comprising a data entry ID, a data entry version identifier, and a data payload representing operating information of the controller or another controller; a processing unit ( 102 ); a first interface ( 103 ) for communicating with another controller. The controller is configured to transmit a first data packet comprising data entry ID and data entry version identifier of a data entry in the data storage unit, to other controllers; and to receive a second data packet transmitted by said another controller, the second data packet comprising data entry ID and data entry version identifier of a data entry of said another controller; and compare the received data entry version identifier of the second data packet, with a data entry version identifier of a corresponding data entry in the data storage unit having a same data entry ID as the second data packet.

1 . A conveyor system controller comprising:
 a data storage unit configured to store a plurality of data entries, each data entry comprising a data entry ID, a data entry version identifier, and a data payload representing operating information of the controller or another controller;   a processing unit; and   a first interface for communicating with said another controller;   wherein the controller is configured to   transmit a first heartbeat data packet comprising data entry ID and data entry version identifier of a data entry in the data storage unit, via the first interface, to other controllers;   receive a second heartbeat data packet transmitted by said another controller, via the first interface, the second heartbeat data packet comprising data entry ID and data entry version identifier of a data entry of said another controller; and   compare the received data entry version identifier of the second heartbeat data packet, with a data entry version identifier of a corresponding data entry in the data storage unit having a same data entry ID as the second heartbeat data packet;   wherein, when the controller determines that the data entry stored in its storage unit is newer than the corresponding data entry in said another controller, the controller is configured to transmit to said another controller a first synchronizing data packet comprising the data entry ID, the data entry version identifier, and at least a portion of the data payload, of the corresponding data entry in the data storage unit;   wherein a size of the first synchronizing data packet is greater than a size of the first heartbeat data packet;   the controller is further configured to receive a second synchronizing data packet comprising a second data entry ID, a second data entry version identifier, and at least a portion of a second data payload, of a second data entry in said another controller's data storage unit,   wherein a size of the second synchronizing data packet is greater than a size of the second heartbeat data packet,   wherein, when the second data entry version identifier of the second synchronizing data packet is indicated as newer than a data entry version identifier of a corresponding data entry in the data storage unit, the controller is configured to update the data payload and the data entry version identifier of the corresponding data entry in the data storage unit, according to the portion of the second data payload and the second data entry version identifier of the second synchronizing data packet;   wherein the controller further comprises a second interface for communicating with an external unit;   wherein the controller is further configured to:   receive a first signal from the external unit, via the second interface, for updating a data payload of a data entry in the data storage unit;   update the data payload of the data entry in the data storage unit according to the first signal; and   update the data entry version identifier of the updated data entry to indicate a newer version.   
     
     
         2 . (canceled) 
     
     
         3 . The conveyor system controller as claimed in  claim 1 , wherein the controller is configured to determine that the data entry stored in its storage unit is newer than the corresponding data entry in said another controller based on a change in its data payload and/or a change in its data version identifier. 
     
     
         4 . The conveyor system controller as claimed in  claim 1 , wherein the controller is configured to determine that the data entry stored in its storage unit is newer than the corresponding data entry in said another controller based on that the data entry version identifier of the second heartbeat data packet is indicated as older than the data entry version identifier of the corresponding data entry in the data storage unit. 
     
     
         5 . The conveyor system controller as claimed in  claim 1 ,
 wherein the controller is configured such that the first synchronization data packet comprises a portion of the data payload, said portion being a subset of the data payload,   wherein the first synchronization data packet further comprises an indication of total data payload size for the data entry and/or a data payload portion order indicator.   
     
     
         6 . The conveyor system controller as claimed in  claim 1 , wherein the controller is configured to transmit the first heartbeat data packet only for data entries that meet a predetermined criterion, such as a data entry ID or a data entry ID range. 
     
     
         7 . The conveyor system controller as claimed in  claim 1 , wherein the controller is configured to receive said heartbeat second data packet only if the data entry ID of the second heartbeat data packet meets a predetermined criterion, such as a data entry ID or data entry ID range. 
     
     
         8 . (canceled) 
     
     
         9 . The conveyor system controller as claimed in  claim 1 , wherein the controller is further configured to:
 provide a second signal to the external unit, via the second interface, for controlling the external unit.   
     
     
         10 . (canceled) 
     
     
         11 . The conveyor system controller as claimed in  claim 1 , wherein the data entry version identifier comprises a counter or a time stamp. 
     
     
         12 . The conveyor system controller as claimed in  claim 1 , wherein the operating information comprises an operating mode, such as a controller configuration, and/or an operating status, such as a sensor state or an error state. 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . (canceled) 
     
     
         17 . A method of data synchronization between a plurality of conveyor system controllers of a conveyor system,
 wherein each conveyor system controller comprises:   a data storage unit configured to store a plurality of data entries, each data entry comprising a data entry ID, a data entry version identifier, and a data payload representing operating information of the controller or another controller;   a processing unit; and   a first interface for communicating with said another controller;   the method comprising, in each controller:   transmitting a first heartbeat data packet comprising data entry ID and data entry version identifier of a data entry in the data storage unit, via the first interface, to other controllers;   receiving a second heartbeat data packet transmitted by said another controller, via the first interface, the second data packet comprising data entry ID and data entry version identifier of a data entry of said another controller; and   comparing the received data entry version identifier of the second heartbeat data packet, with a data entry version identifier of a corresponding data entry in the data storage unit having a same data entry ID as the second heartbeat data packet;   wherein, when the controller determines that the data entry stored in its storage unit is newer than the corresponding data entry in said another controller, the method comprises:   transmitting to said another controller a first synchronizing data packet comprising the data entry ID, the data entry version identifier, and at least a portion of the data payload, of the corresponding data entry in the data storage unit;   wherein a size of the first synchronizing data packet is greater than a size of the first heartbeat data packet;   receiving a second synchronizing data packet comprising a second data entry ID, a second data entry version identifier, and at least a portion of a second data payload, of a second data entry in said another controller's data storage unit,   wherein a size of the second synchronizing data packet is greater than a size of the second data packet, and   when the second data entry version identifier of the second synchronizing data packet is indicated as newer than a data entry version identifier of a corresponding data entry in the data storage unit, the method further comprises updating the data payload and the data entry version identifier of the corresponding data entry in the data storage unit, according to the portion of the second data payload and the second data entry version identifier of the second synchronizing data packet;   wherein each controller further comprises a second interface for communicating with an external unit;   wherein the method comprises, in each controller:   receiving a first signal from the external unit, via the second interface, for updating a data payload of a data entry in the data storage unit;   updating the data payload of the data entry in the data storage unit according to the first signal; and   updating the data entry version identifier of the updated data entry to indicate a newer version.   
     
     
         18 . (canceled) 
     
     
         19 . (canceled) 
     
     
         20 . (canceled) 
     
     
         21 . (canceled)